We built 8 AI-powered SaaS products in 2025. Here is the exact stack, costs, and timeline for each.

By David Friedman , Founder of AppBrewers

AI is not a feature anymore. It is the product. We built 8 AI-powered SaaS products in 2025. Some failed. Three are profitable. Here is the exact stack, costs, and timeline that worked.

What "AI-Powered SaaS" Means in 2026

Type AI Role Example Complexity

AI wrapper UI around GPT-4 Writing assistant Low

AI agent Multi-step reasoning Research assistant Medium

AI copilot Context-aware suggestions Code reviewer Medium

AI platform Custom models + training Image generator High

AI automation Workflow execution Invoice processor Medium

Tech Stack

Layer Technology Cost Why

Frontend Next.js 15 Free App Router, streaming, SEO

Backend Next.js API routes / Firebase Free - 200 Euro Serverless, scalable

AI model OpenAI GPT-4o / Claude 3.5 20-500 Euro/month Best reasoning, fastest

Vector DB Pinecone / Weaviate / Supabase 0-100 Euro/month RAG, semantic search

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